padilla36

Can any one help me.
I have an 87 z28 350 tpi and im getting codes 22 and 23.
I have adjusted the tps to get the proper voltage= .578 and my car is still idles rough and my ses light comes on.
I havent tried anything for code 23
Please help!

BigBadLou

Code 23 is for a low reading from the IAT/MAT sensor.
It is common, when you see this code, that the sensor is disconnected.
It is located on the BOTTOM of the upper intake plenum, in the back, toward the driver side. It should have a two-wire connector and the wires should run to the back of the engine via another connector.
Locate the sensor and let us know what you find, we'll take it from there.

Code 22 is for low TPS voltage, you are right. However, it does not necessarily have to be a low constant voltage, it could be very intermittent. Check the wires for fraying, breaks, oxidation. Monitor the votlage as you wiggle the wires, looking for voltage drops.
You can also test the TPS voltage at the ECM, pin C13 (dark blue wire).
Let us know what you find.

Hope this helps.
Lou

Z28SORR

Have you checked the "general" voltage, bat. and alt.